Question

f(x) = 3x - 7 and g(x) = -2x - 6. Find (f o g)(4)
Please help!?

Answer 1

First plug in

g(x)=-2x-6 in f(x)=3x-7 in place of x :)

Answer 2

So would it be f(x) = 3(-2x - 6) - 7 ?

Answer 3

Yes

f(g(x))=3(-2x-6)-7

Now put 4 in place of x and get

(fog)(4)=..
or

f(g(4))=..

Answer 4

Okay, so would it be f(g(4)) = -49 ?

Answer 5

Yeah right :)

Answer 6

Okay Thank you! could you help me with one more please ?

Answer 7

Sure :)

Answer 8

Okay, Rewrite \[\sqrt[3]{27x - 81} - 5\] to make it easy to graph using a translation. Describe the graph

Answer 9

I know that you would put 1/3 as an exponent but I don't know where

Answer 10

Well see this.

\[\huge\ \sqrt[3]{a}=(a)^{1/3}\]

Another example,

\[\huge\ \sqrt[3]{x-2}=(x-2)^{1/3}\]

Answer 11

Okay so it would be (27x - 81)^1/3 - 5, right ?

Answer 12

Yes we can work more on it if you want :)

Answer 13

Yes please! Would this be the equation to make it easier to graph or is there more ?

Answer 14

Yes lets continue then take the 27 common.

\[\huge\ [27(x-1)]^{1/3}-5 \]
\[\huge\ [3^3 (x-1)]^{1/3}-5\]

Answer 15

Now you can cancel.


\[\huge\ (x^3)^{(1/3)}=x\]

Answer 16

Okay, is this what the equation is or is this just stating what x equals ?

Answer 17

I am showing you how you can cancel.

Answer 18

The above statement was an example.

Answer 19

Oh okay

Answer 20

\[\huge\ [3^3 (x-1)]^{1/3}-5\]


Can you further simplify this ?

Answer 21

Wait, I am not sure how you did the (x^3) ^1/3 = x

Answer 22

Would it be (9x - 1)^1/3 - 5 ? @hba

Answer 23

No.

Answer 24

I'm confused :/

Answer 25

\[\huge\ (3^3)^{1/3} ((x-1))^{1/3}-5\]Now can you do it ?

Answer 26

Lets see... (3^3)^1/3 would become just 3 correct?

Answer 27

Yeah :)

Answer 28

Okay so it would be 3(x - 1) - 5 ? or would I combine 3 and x - 1?

Answer 29

No.

3 (x-1)^{1/3}-5

Answer 30

Oh, I forgot the 1/3 sorry

Answer 31

Then what would I do?

Answer 32

Have some ice-cream :)

Can i get some cookies ?

I am the cookie monster.

Answer 33

C is for cookie and cookie is for me.

P.S. I am out of cookies :'(

Answer 34

Wait, is that the answer ?

Answer 35

Yeah LoL

Answer 36

Oh haha, then I would just graph it and describe what it looks like right ?

Answer 37

I've got some cookies lol (:

Answer 38

cookies LoL :P

Yeah you can graph it :)

Now it is easy i guess :)

Answer 39

Okay lol, Thank you for your help!

Answer 40

Welcome Welcome :)